himu wrote:Is x^2 > 4x - 3y?

(1) y > 0 and x > 4

(2) 4x - 3y = -1

Target question: Is x^2 > 4x - 3y?

Statement 1: y > 0 and x > 4
To determine whether or not this statement is sufficient, it may be useful to first rephrase the target question.
First move all all terms to one side to get: Is x^2 - 4x + 3y > 0?
Factor the first 2 terms to get: Is x(x-4) + 3y > 0?

At this point, we'll use the given information.
If y>0, then 3y>0 (in other words 3y is positive)
If x>4, then (x-4)>0 and x>0 (in other words, x-4 and x are both positive)
If 3y, x-4 and x are all positive, then x(x-4) + 3y must be greater than 0
So, statement 1 is SUFFICIENT

Statement 2: 4x - 3y = -1
This one is a little more straightforward.
Here, we'll use the original target question: Is x^2 > 4x - 3y?
If 4x - 3y = -1, we'll replace take the target question and replace 4x - 3y with -1 to get: Is x^2 > -1
Since x^2 must be greater than or equal to zero, it must be the case that x^2 > -1
As such, statement 2 is SUFFICIENT, and the answer is D

Cheers,
Brent